Slack-take-up for valve mechanism



a .4 V, flag/42727194? June 5, 1923.

E. W. CAULFIELD SLACK TAKE-UP FOR VALVE MECHANISM Filed May 1, 1920 Fizz/arr] W ("a Patented June 5, 1923.

PATENT-1: FFICE.

EDWARD W. CAULFIELD, OF TAYLOR, TEXAS.

SLACK-TAKE-UP FOR VALVE MECHANISM.

Applicatgn. filed May 1,

- To all whom it may concern:

Be it known that I, EDWARD V. CAULFIELD,

a citizen of the United States, residingat Taylor, county of Williamson, in the State 6 of Texas, have invented certain new and useful Improvements in Slack-Take-Ups for "Valve Mechauisnfiof which the following is a specifi catiorif I My invention relates to valve actuating mechanism for internal combustion engines. More s ecifically my invention relates to slackta e-up for such mechanism.

The object of my invention is to provide a valve actuating mechanism with means for taking up slack therein, to the end that the rattling and vibration in said mechanism shall be eliminated. A further object of my invention is to provide a slack take-up which may be readily applied to the engine without necessitating any change whatever in the valves, rocker arms or cam shaft. A further object of my invention is to provide a device as mentioned which will automatically take up the slack in the valve actuating mechanism, and which will not jam or cause injury to the engine or to the take-up should the valve stick. Further objects of my invention are to provide a device as mentioned which will be of simple construction, of low cost to 'manufacture, neat in appearance, easily applied and adjusted, which will not readily get out of order. Qther objects will appear hereinafter.

With these objects in view my invention consists generally in providing an extensible valve actuating rod between the cam shaft and the valve operating rocker arm, and means for yieldingly holding the rod in extended position. My invention further consists in a device .as mentioned further characterized by means permitting free extension of the rod within limits, and to prevent contraction of the same. My invention furmentioned 'in combination with means to limit the extension of the rod beyond certain limits to avoid damage should the valve become stuck. My invention further consists in various details of construction and arrangements of parts all as will be fully described hereinafter and particularly pointed out in the claims. l

My invention will be more readily underther consists in a device of the character i920. Serial No. 378,109.

stood by reference to the accompanying drawings forming a part of this specification and in which Fig. l is a side elevation of a slack take.- up embodying my invention, the cam shaft, the valve stem and rocker arm of an en gine being illustrated diagrammatically with relation thereto.

Fig. 2 is a longitudinal sectional view of the same upon an enlarged scale, and,

Fig. 3 is a transverse section on line 33 of Fig. 2-

Referring now to the drawings. 1 indiu cates a portion of the engine, 2 a valve stem normally held in elevated position by a spring 3,and 4 the valve actuating rocker arm supported upon a shaft 5. 6 indicates the cam shaft. These portions of the device, of themselves, form no part of my invention as they are the usual parts of a modern internal combustion engine, and may be of any preferred form provided the rocker arm 4 is actuated by impacts from the cam shaft through a valve rod interposed between the cam shaft and rocker arm.

7 indicates a valve rod the up er end of which is equipped with a ball fitting within the socket 9 in one arm of the rocker 4. The ball end .8 is 'adjustably secured to the rod 7 in the. usual manner, that is, by being threaded upon the end 9 as indicated clearly in Fig. 2 of the drawings. of the rod 7 extends within a ta ered cup 10, said cup terminating in a. depending stem' 11 which is mounted in an extension 12 carrying a roller 13 which is engaged by the cam of the cam shaft 6. The stem 11 is provided with a bore 14 to receive the extreme lower end of rod 7. 15 indicates a stop or washer on the rod 7 and 16 a spring interposed between said Washer and the cup 10. A cotter pin 17 or other suitable means, limits the upward movement of the washer 15. By this construction it Will be seen that the spring 16 normally tends to extend the length of the rod 7 and keep the ends thereof, or more specifically the ball 8 and roller 13, firmly in contact with the arm 4 and cam shaft 6, respectively.- It is also obvious that the spring 16 would not be sufficient to impart the necessary positive movement to the rocker arm, and hence it is nec essary to provide means to prevent contrac- The lower end the wall of tion of the length of the -rodwhilethe enpered, it is obvious that the balls 20, upon the application of forceto either end of the rod 7 will jam between the rod and the cup preventing contraction of the rod in length. The cup 10 is-provided with a closure 21 held in' place by any suitable means such as a split ring 22 sprung into a groove 23 as illustrated in Fig. 2 a spring 24 is interposed between the closure 21 and the cage 19. The spring normally depresses the cage and holds the balls in'contact with both the cup 'lO'and rod 7. Obviously, with this construction, the rod 7 willmove freely outwardly under the action of the spring 16 but will be prevented fromcontracting in length by the balls 20. Should the valve become struck, so that the spring 3 will not return the arm 4 upon retraction of the rod 7, the rod would be extended inlength and upon re-engagement of the cam with the roller 13,- the valve actuating mechanism would become damaged. To avoid this, I provide means to limit the free'extension the rod 7. To this end a suitable stop, such as cotter pin 25 is provided on the rod 7 a short distance below the cage 19. It is obvious that upon wearing of the parts the spring 16 will extend the length of the valve rod totake up the slack until the stop 25' engages the cage 19. Readjustment of the rod may be readily accomplished by contracting the length of the rod and extending the portion 8 thereof. To contract the rod inlength the cage 19 must first be lifted, and to facilitate lifting the cage, the sleeve 18 is provided with a shoulder 26 which may be readily engaged by any suitable tool for this purpose. After the end 8 is extended the parts are released and the spring 16 will again bring the end of the rod firmly into engagement with their respective co-operating elements. It .will be noted that the entire slack adjusting device is contained within the valve rod 7 so that any engine having the rocker arms and cam shaft related in a manner similar to that shown in the drawings, may be readily equipped with my invention without makv ves, rocker arms, or vcam shaft. The only operation necessary is to remove the usual valve rod and replace the same with one equipped with my invention.

I claim 1. In an internal combustion engine hav-- -1ng a valve actuating rocker arm and cam shaft, a valve rod-,interposed between sa1d terposed between said cup and the other part of the rod, substantially asdescribed.

2. A device as set forth in claim 1 in which said ball clutch comprises a cage freely slidable upon one of the, rod portions, balls carried thereby, and a spring normally actuating said cage to hold the balls in engagement with said cup and the other portion of the rod, substantially as described.

3. In an' internalcombustion engine equipped with a valve actuating rocker arm and cam shaft, in combination with a valve rod interposed between said cam shaft and.

rocker arm, said rod comprising an upper rod portion and a lower cam shaft engaging portion, a tapered cup on saidlowe'r portion to receive the lower end of'the upper portion, a sleeve slidable on the upper portion and provided with a ball cage, and balls interposed between said cup and said upper portion, and

a spring interposed between the upper and lower portions ofsaid'rod constantly tending to extend the length thereof, substantially as described.

-. 4. A device as set forth in claim 3, further characterized by-a spring maintaining said balls in operative position, substantially as described. v

5. A device as set forth in claim 3, further characterized by a stop on the upper portion of said rod-below the said sleeve, substantially as described.

6 In an internal com'busion engine, a valve actuating rod comprising portions longitudinaly movable with relation to each other, a tapered cup on one of said portions, anda ball clutch interposed between said cup and the other portion of the rod,

, ing the stem and cage member in adjusted in any alterations in the engine, itself, the

positions.

9. An attachment for valve stems comprising a cage, a sleeve mounted therein, a

spring -located in said cage member for holding said sleeve in projected position,

and means associated with said sleeve and adapted to cooperate therewith to bind the cage and a valve actuating stem in adjusted positions. Y

10. An attachment for valve com-' prising a cage member, a sleeve slidably mounted therein, and means comprising inclined portions and balls for binding the cage and a valve actuating stem in adjusted positions. a

11. An attachment for valve stems comprising a cage member, a sleeve slidably mounted therein, a spring vlocated in said cage for holding said sleeve in projected. position, and means comprising inclined 15 portions and balls for bindlng the cage and a valve actuating stem in adjusted positions. In testimony whereof I have signed 'my name to this specification in the presence of two subscribing Witnesses.

EDWARD W. CAULFIELD. Witnesses:

HOWARD S. AUSTIN, F. CHATLIN. 

